Process for recovering rubber waste.



JOHN D. M

ployed and also in the GOMRANY, CORPQR'ATION OF OHIO.

, EAST CLEVELAND, JOHN D. MoRRoN, CHARLns R. HAYNES, 0F CLEVELAND, OHIO,

OF-LAKEWQOD, AND ASSIGNORS TO MECHANICAL RUBBER rRoCEss roR RBCCVERING RUBBER WASTE.

No Drawing.

To all whom it may concern.-

Be it known that we, RICHARD F. KINSLEY, ORRON, and CHARLES R. HAYNES, all citizens of the United States, and residents, respectively, of East Cleveland, Lakewood, and Cleveland, inthe county of Guyahoga, State of Ohio, have jointly invented certain new and useful Improvements in Processesfor Recovering Rubber Waste, of which the following is a full, clear, and exact description.

This invention relates recovery and utilization scrap, containing fibrous material which is produced by clippings in the manufacture of such articles as rubber hose, belting, packing, tire fabrics, rubber boots, shoes and other articles of mechanical use, or of clothing. Similar worn or discarded articles may also be treated and the rubber and fibrousmaterial utilized and recovered by our improved process.

The object of our invention is to produce a process which will result in a material saving in ingredients and chemicals emamount of labor, power, heat, washing and other handling, such as required in other processes heretoparticularly .to the of rubber waste or fore in use. Other advantages will be more specifically pointed out hereinafter and the process from which they result will be claimed in the claims forming a part of this specification. I

In reclaiming rubber containing fabric and similarv materials, in accordance with this invention, mascerating the material, after which it is placed in a large tank or tub. Such tank may be in the form of a'vat which is heated in any well-known way and whichis provided with an opening in the bottom to draw off the contents; next, the material ismixed with furic acid in the vat. A 25% solution of acid is preferred, but this may be varied to suit different conditions, depending upon the composition of the waste to be treated.

he mass is then heated until the fiber in the-' rubber mass is disintegrated and its fibrous nature destroyed. The contents of the tank is then neutralized by the addition of a suitable base of the alkaline earths, such as powdered lime, the amount of'lime requlred being adapted to change the sulfuric Specification of Letters Patent.

' with with it, is caught in suitable receptacles and mass and the the process comprises: First,

an aqueous solution of sulsulfate and water. A slight excess of basic material is added in order that no traces of free acid may remain in the compound. The addition of this dry powder very nearly absorbs all the moisture or water in the mixture and any surplus which may remain in the mixture is drawn off through a suitable opening in the vat or tank. This water, whatever chemicals may be carried the rest of the mixture is removed from the -vat and spread on a suitable drying floor to facilitate its further working. The liquor previously drawn off is then added to the whole worked together until it is substantially homogeneous. The mixture is allowed to dry until it contains a small amount of moisture, eight to ten per Patented Feb.'1l3,l91'?.' Application filed February '1, 1915. Serial No. 5,507.

cent. having been found in actual practice to give good results, and then is mixed. with a devulcanizing agent containing as one of its ingredients, a saponifiable oil. vulcanizing agent may consists of a heavy mineral oil or addition of resins or bituminous substances, together with a saponifiable oil, such as corn oil. During the step of devulcanization, theexcess of lime or other alkali radi- This degrease. with or without the cals present acts upon the oil, saponifying it and as a result there is linity in the mixture.

After thus preparing the compound, the mass of materialwhich now consists of an intimate mixture of devulcanized rubber compound, the various added chemicals and reagents and the products of their reactions, and a disintegration product made from the fibrous material present in the original substances,is worked up to a manufacturing consistency by being dried and refined in a manner similar to other well known methods of handling devulcanized rubber compounds. It will be apparent that the sul fate radical of the acid and the disintegration product of the fiber might be recovered after treatment in tation'with lime in a setting tank, and removing the sludge, and filtering and drying it, but we prefer to accomplish substantially the same effect by simply adding the alkali and making use of, the heat of chemipractically no alkacal reactions.

By'this process none of the ingredients the acid vat, by precipi- 'methods is also very low,

required for washing and agitation power consumed 'by the necessary while washing. Extraneous heat is not required for drying because of the heat of chemical reaction, which is sufiicient to produce evaporation to a great extent, and also because the liquid ingredients are nearly all converted to solids or,vapors by such reactions.

What we claim and desire to protect by Letters Patent is: v

1. The process of recovering rubber waste containing fibrous material, which comprises treatment with acid and then neutralizing the acid with a suitable basic material, leavin within the mass so treated substantially .all the added ingredients and the products of their reactions, except an excess of moisture. 1

2. The process of recovering rubber waste containing fibrous material, which comprises treatment with an acid, neutralizing the acid with a suitable basic material added in excess of the amount required to neutralize the acid, and then mixing therewith a substance which converts said excess of said basic material into a product not deleterious to rubber. i

3. The process of recovering rubber waste containing fibrous material, which comprises subjecting the same to the action of an acid, neutralizin the acid with a suitable basic material a ded in excess of the amount required to neutralize the acid, and then mixing therewith a substance which converts said excess of said basic material into a, product not deleterious to rubber, leaving within the mass so treated, substantially all the added ingredients and the products of their reactions, except an excess of moisture.

4. The process of recovering rubber waste mass, evaporating containing fibrous material, which comprises disintegratingthe fibrous material by treatment with acid, adding a suitable base of an alkaline earth in excess of the amount sufiicient to neutralize the acid, and then adding saponifiable oil to be saponified by the excess of said base and to eifect devulcanization.

5. The process of recovering rubber waste containing fibrous material, which comprises dividing the waste into small particles, disintegrating the fibrous material by treatment with acid, neutralizing the acid with a suitable base of an alkaline earth, working the resultant solid and liquid components into a homogeneous. mass, and then adding adevulcanizing agent and a saponifiable oil.

6. The processof recovering rubber waste containing fibrous material, which comprises dividing the waste into small particles, disintegrating the fibrous material by adding sulfuric acid, neutralizing the acid by the addition of a base of an alkaline earth in powdered form, working the resultant solid and liquid components into a homogeneous mass, and then adding a devulcanizing agent and a saponifiableoil.

7 The process of recovering rubber waste containing fibrous material, which comprises dividing the waste into small particles, disintegrating the fibrous material by adding sulfuric acid, neutralizing the acid by the addition of a powdered form, working the resultant solid and liquidcomponents into a homogeneous the same to a point leaving about ten per cent. moisture and then adding a devulcanizing agent and a saponifiable oil.

Signed this 25th day of January, 1915.

RICHARD F. KINSLEY.

JOHN D. MORRON. CHARLES R. HAYNES.

Witnesses:

W. J. DENCKER, W. S. WESTWOOD.

base of an alkaline earth in 

